Each of these choices has their advantages and disadvantages. Gold fillings are the strongest and most durable, but they are also the most expensive choice, most complicated to perform (additional visit to the dentist are required), aesthetically not pleasing and can cause galvanic shock. Amalgam fillings are also very strong and durable as gold filling, but much less expensive. Unfortunately, they have very poor aesthetics, they can cause cracks and fractures in the tooth, healthy parts of the tooth need to be removed in order to place the filling and due to the mercury in the amalgam, about 1% of people have allergic reactions to this filling. Composite resin fillings have the best aesthetics, are non-invasive and have great bonding to the tooth. They are also less durable and can be chipped and worn of much sooner than metal-based fillings. The technology of these materials is constantly advancing, but still there is no consensus among dentist which is the best.